more questions about VC monomer and PVC

["Jon Campbell" <jon@cqs.com>]

  Dr.Bill,
  
      I wonder if you could satisfy my curiosity
  about VC monomer and PVC. You mentioned
  that the PVC industry had begun "stripping"
  VC monomer from PVC some time ago, and I
  was wondering if you knew:
  
  1. What year was this accomplished (approx).
  2. What was the approx VC-M contamination level
  in PVC before and after the technology was deployed?
  3. Do the offshore PVC manufacturers (notably
  China, Hong Kong, Korea, Vietnam, and Singapore)
  use this technology?
  
  Thanks very much
  Jon